refactor: loadFrameworkPaths -> getEggPaths

Load order has changed from `app > framework > plugin > egg`
to `app > framework(contain egg) > plugin`

Remove options.eggPath, egg is one of the framework.

Remove options.customEgg, every framework should specify `Symbol.for('egg#eggPath')`

Author: popomore

lib/base_loader.js

@@ -7,24 +7,25 @@ const isFunction = require('is-type-of').function;
 const interopRequire = require('interop-require');
 const debug = require('debug')('egg:loader');
 const Loader = require('./loader');
+const Emitter = require('events').EventEmitter;
 
 class EggLoader {
 
   /**
    * @constructor
    * @param {Object} options
    * - {String} [baseDir] - 应用根目录
-   * - {String} [eggPath] - 使用 egg-loader 的框架的路径，如 egg
-   * - {String} [customEgg] - 自定义入口框架的路径，每个异构技术 bu 都可以自定义自己的插件集合
-   * - {Object} [plugins] - 自定义插件配置，测试用
    * - {Object} [app] - app 实例，如果是 Agent Worker 则传入 agent 实例，可为空
+   * - {Object} [plugins] - 自定义插件配置，测试用
    * - {Logger} [logger] - logger 实例，默认是 console
    */
   constructor(options) {
-    this.options = options || {};
+    options = options || {};
+    assert(fs.existsSync(options.baseDir), `${options.baseDir} not exists`);
+
+    this.options = options;
     this.options.logger = this.options.logger || console;
     this.app = this.options.app || {}; // master 没有 app
-    assert(fs.existsSync(this.options.baseDir), `${this.options.baseDir} not exists`);
 
     /**
      * 读取 package.json
@@ -33,48 +34,22 @@ class EggLoader {
     this.pkg = require(path.join(this.options.baseDir, 'package.json'));
 
     /**
-     * 初始化时传入，见 {@link EggLoader}
-     * @member {String} EggLoader#eggPath
-     */
-    this.eggPath = fs.realpathSync(this.options.eggPath);
-    debug('Loaded eggPath %j', this.eggPath);
-
-    /**
-     * 框架可以继承，从入口框架(CustomEgg)找到所有的框架的根目录
-     *
-     * 需要通过配置 getter 来指定 eggPath 才能被加载到
-     *
-     * ```
-     * // lib/xx.js
-     * const egg = require('egg');
-     * class XxApplication extends egg.Application {
-     *   constructor(options) {
-     *     super(options);
-     *   }
-     *
-     *   get [Symbol.for('egg#eggPath')]() {
-     *     return path.join(__dirname, '..');
-     *   }
-     * }
-     * ```
-     * @member {Array} EggLoader#frameworkPaths
-     */
-    this.frameworkPaths = this.loadFrameworkPaths();
-    debug('Loaded frameworkPaths %j', this.frameworkPaths);
-
-    /**
-     * = this.eggPath + this.frameworkPaths
      * @member {Array} EggLoader#eggPaths
+     * @see EggLoader#getEggPaths
      */
-    this.eggPaths = [ this.eggPath ].concat(this.frameworkPaths);
+    this.eggPaths = this.getEggPaths();
     debug('Loaded eggPaths %j', this.eggPaths);
 
+    /**
+     * @member {String} EggLoader#serverEnv
+     * @see EggLoader#getServerEnv
+     */
     this.serverEnv = this.getServerEnv();
     debug('Loaded serverEnv %j', this.serverEnv);
   }
 
   /**
-   * Get environment of Egg, it's not NODE_ENV
+   * Get environment of Egg, **it's not NODE_ENV**
    *
    * 1. from `$baseDir/config/serverEnv`
    * 2. from EGG_SERVER_ENV
@@ -115,6 +90,53 @@ class EggLoader {
     return serverEnv;
   }
 
+  /**
+   * Get all framework directories.
+   *
+   * You can extend Application of egg, the extrypoint is options.app,
+   *
+   * loader will find all directories from the prototype of Application,
+   * you should define `Symbol.for('egg#eggPath')` property.
+   *
+   * ```
+   * // lib/xx.js
+   * const egg = require('egg');
+   * class XxApplication extends egg.Application {
+   *   constructor(options) {
+   *     super(options);
+   *   }
+   *
+   *   get [Symbol.for('egg#eggPath')]() {
+   *     return path.join(__dirname, '..');
+   *   }
+   * }
+   * ```
+   *
+   * @return {Array} framework directories
+   */
+  getEggPaths() {
+    const eggPaths = [];
+
+    let proto = this.app;
+    while (proto) {
+      proto = Object.getPrototypeOf(proto);
+      if (proto) {
+        if (isKoa(proto)) {
+          break;
+        }
+        const eggPath = proto[Symbol.for('egg#eggPath')];
+        assert(eggPath, 'Symbol.for(\'egg#eggPath\') is required on Application');
+        // 使用 fs.realpathSync 来找到最终路径
+        const realpath = fs.realpathSync(eggPath);
+        if (eggPaths.indexOf(realpath) === -1) {
+          eggPaths.unshift(realpath);
+        }
+      }
+    }
+
+    return eggPaths;
+  }
+
   /**
    * 加载自定义的 app.js，**在 app.js 可做任何操作，但建议尽量减少此操作，做该做的事**。
    *
@@ -209,9 +231,6 @@ class EggLoader {
 
     const dirs = this.dirs = [];
 
-    // egg 本身路径，在 lib/core 目录下
-    dirs.push(path.join(this.eggPath, 'lib/core'));
-
     // 插件目录，master 没有 plugin
     if (this.orderPlugins) {
       for (const plugin of this.orderPlugins) {
@@ -220,8 +239,8 @@ class EggLoader {
     }
 
     // egg 框架路径，在 lib/core 目录下
-    for (const frameworkPath of this.frameworkPaths) {
-      dirs.push(path.join(frameworkPath, 'lib/core'));
+    for (const eggPath of this.eggPaths) {
+      dirs.push(path.join(eggPath, 'lib/core'));
     }
 
     // 应用目录
@@ -231,42 +250,6 @@ class EggLoader {
     return dirs;
   }
 
-
-  /**
-   * 获取 {@link EggLoader#frameworkPaths}
-   * @return {Array} 框架目录
-   * @private
-   */
-  loadFrameworkPaths() {
-    const eggPath = this.eggPath;
-    const frameworkPaths = [];
-
-    addEggPath(this.options.customEgg);
-
-    // 遍历整个原型链，获取原型链上所有的 eggPath
-    // 越核心的优先级越高
-    let proto = this.app;
-    while (proto) {
-      proto = Object.getPrototypeOf(proto);
-      if (proto) {
-        const eggPath = proto[Symbol.for('egg#eggPath')];
-        addEggPath(eggPath);
-      }
-    }
-
-    return frameworkPaths;
-
-    function addEggPath(dirpath) {
-      if (dirpath) {
-        // 使用 fs.realpathSync 来找到最终路径
-        const realpath = fs.realpathSync(dirpath);
-        if (frameworkPaths.indexOf(realpath) === -1 && realpath !== eggPath) {
-          frameworkPaths.unshift(realpath);
-        }
-      }
-    }
-  }
-
   /**
    * 返回应用 appname，默认获取 pkg.name
    *
@@ -316,3 +299,9 @@ for (const loader of loaders) {
 }
 
 module.exports = EggLoader;
+
+function isKoa(app) {
+  return app.hasOwnProperty('use') &&
+    app.hasOwnProperty('listen') &&
+    Object.getPrototypeOf(app) === Emitter.prototype;
+}

lib/loader.js

@@ -93,13 +93,11 @@ function getProperties(filepath, lowercaseFirst) {
   return filepath
   .replace('.js', '')
   .split('/')
-  .map(function(property) {
+  .map(property => {
     if (!/^[a-z][a-z0-9_-]*$/i.test(property)) {
       throw new Error(`${property} is not match 'a-z0-9_-' in ${filepath}`);
     }
-    let result = property.replace(/[_-][a-z]/ig, function(s) {
-      return s.substring(1).toUpperCase();
-    });
+    let result = property.replace(/[_-][a-z]/ig, s => s.substring(1).toUpperCase());
     if (lowercaseFirst) {
       result = result[0].toLowerCase() + result.substring(1);
     }

lib/loader/config.js

@@ -1,61 +1,13 @@
 'use strict';
 
 require('should');
-const path = require('path');
 const mm = require('mm');
 const utils = require('./utils');
-const BaseLoader = require('../index');
 
 describe('test/egg_loader.test.js', function() {
 
   afterEach(mm.restore);
 
-  describe('eggPaths', function() {
-
-    it('should get from paramter', function() {
-      const app = utils.createApp('eggpath');
-      app.loader.eggPath.should.equal(utils.getFilepath('egg'));
-    });
-
-    it('should get from framework', function() {
-      const Application = require('./fixtures/framework');
-      const app = new Application();
-      app.coreLogger = console;
-      app.loader = new utils.Loader('eggpath', { app });
-      app.loader.loadConfig();
-      app.loader.eggPaths.should.eql([
-        utils.getFilepath('egg'),
-        utils.getFilepath('framework/node_modules/framework2'),
-        utils.getFilepath('framework'),
-      ]);
-      return app;
-    });
-
-    it('should get from framework using symbol', function() {
-      const Application = require('./fixtures/framework-symbol');
-      const app = new Application();
-      app.coreLogger = console;
-      app.loader = new utils.Loader('eggpath', { app });
-      app.loader.loadConfig();
-      app.loader.eggPaths.should.eql([
-        utils.getFilepath('egg'),
-        utils.getFilepath('framework-symbol/node_modules/framework2'),
-        utils.getFilepath('framework-symbol'),
-      ]);
-      return app;
-    });
-
-    it('frameworkPaths should not container eggPath', function() {
-      const eggPath = path.join(__dirname, 'fixtures/egg');
-      const loader = new BaseLoader({
-        baseDir: path.join(__dirname, 'fixtures/eggpath'),
-        eggPath,
-        customEgg: eggPath,
-      });
-      loader.frameworkPaths.should.not.containEql(eggPath);
-    });
-  });
-
 
   describe('loadDirs', function() {
 

test/egg_loader.test.js

@@ -6,7 +6,7 @@ module.exports = function(app) {
       customFoo: app.customFoo,
       env: app.config.env,
       eggPaths: app.loader.eggPaths,
-      frameworkPaths: app.loader.frameworkPaths,
+      eggPaths: app.loader.eggPaths,
       eggPath: app.loader.eggPath,
     };
   });

test/fixtures/custom-app/app/router.js

@@ -1,9 +1,11 @@
 'use strict';
 
-module.exports = require('../../../');
-const startCluster = module.exports.startCluster;
+const KoaApplication = require('koa');
 
-module.exports.startCluster = function(options) {
-  options.customEgg = __dirname;
-  return startCluster(options);
-};
+class Application extends KoaApplication {
+  get [Symbol.for('egg#eggPath')]() {
+    return __dirname;
+  }
+}
+
+module.exports = Application;

test/fixtures/custom-framework/index.js

@@ -0,0 +1,12 @@
+'use strict';
+
+const path = require('path');
+const KoaApplication = require('koa');
+
+class EggApplication extends KoaApplication {
+  get [Symbol.for('egg#eggPath')]() {
+    return __dirname;
+  }
+}
+
+module.exports = EggApplication;

test/fixtures/egg/index.js

@@ -0,0 +1,3 @@
+{
+  "name": "egg"
+}